Silicon‐Containing Cycloaliphatic Epoxy Resins with Systematically Varied Functionalities: Synthesis and Structure/Property Relationships

Abstract

The manipulation of the properties of cycloaliphatic epoxy resins by systematical variations of the molecular structure is demonstrated. Specifically, four cycloaliphatic epoxy resins with silicon‐center linked via methyl, phenyl, and epoxy groups of different number were synthesized. The cured epoxides had remarkably changed crosslinking density from 0.45 × 10−3 to 9.64 × 10−3 mol · cm−3, glass transition temperature from 133 to 237 °C, and considerably decreased thermal expansion coefficient from 6.44 × 10−5 to 4.83 × 10−5 K−1. It was proved that the higher crosslinking density was related to more opened segments by wide‐angle X‐ray diffraction. The physical properties of cured products and their correlations with the chemical structures were investigated in detail.

A One-Component, Fast-Cure, and Economical Epoxy Resin System Suitable for Liquid Molding of Automotive Composite Parts

“…Figure 4 a,b show the storage modulus and the Tan δ, respectively, from which the T g of the neat resin can be determined. It is well understood that the T g of a thermoset resin is mainly affected by intra-molecular stiffness (i.e., molecular rigidity) and cross-linking density [ 5 , 30 , 31 ]. Therefore, for the same thermoset resin system, a higher T g would indicate a higher level of cross-linking.…”

“…In general, imidazoles have intrinsic high curing reactivity towards epoxy resins, and the curing behaviors can be facilely tailored by introducing various substituent groups on the imidazole rings [ 27 , 28 ]. So far, a large number of imidazole hardeners have been designed and commercialized, providing a generous toolbox to develop one-component and fast-curing epoxy systems [ 29 , 30 , 31 ]. In this work, we report an epoxy system (EP-1C2E4MIM) based on diglycidyl ether of bisphenol A (DGEBA) and 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole (1C2E4MIM).…”

Thermal and dielectric properties of nanocomposites prepared from reactive graphene oxide and silicon‐containing cycloaliphatic diepoxide

“…), and acetone were purchased from Shanghai Regent Corporation Ltd. Hexahydro‐4‐methylphthalic anhydride (HMPA) and 2‐ethyl‐4‐methylimidazole (EMI) were used as curing agent and curing accelerator, respectively. Epoxide‐Si was synthesized according to the procedure described in Reference .…”

“…Recently, a series of new silicon‐containing cycloaliphatic epoxides with silicon center linked via methyl, phenyl, and epoxycyclohexyl groups has been developed in our groups . The introduction of a large amount of silicon atoms into epoxy resins brings about excellent comprehensive properties such as outstanding thermal stability, high glass transition temperature, low thermal expansion coefficient, good adhesion strength on various substrates, and low moisture absorption.…”

Epoxy‐Amine Resins with Controlled Reactivity

“…These parameters can be influenced by use of primary or multifunctional amines as curing agents . However, for epoxide‐related control of the kinetics and material properties, novel diepoxides are required and are thus subject to intensive research . So far, diepoxides based on disulfonamides are only barely described in patent literature, although they are easily accessible …”